JP6745095B2 - Damper mounting structure - Google Patents

Description

The present invention relates to a mounting structure for a damping device in a base isolation structure or a vibration control structure.

2. Description of the Related Art Conventionally, oil dampers have been widely used in seismic isolated buildings and damping buildings as a damping device that can obtain a stable damping force.

By the way, when the above oil damper is used as a damping device, if a strong damping force is used assuming a large earthquake, the seismic isolation performance at the time of a small or medium earthquake will deteriorate.
Therefore, as shown in Patent Documents 1 and 2 below, for example, a damping force variable damper has been developed that switches to a stronger damping force than in normal times in the event of a large earthquake.

JP, 2002-310227, A JP, 2009-019383, A

However, in such a damping force variable damper, since a separate detecting means is required to detect the speed and the displacement for switching the damping force, the peripheral device becomes complicated and the inside of the oil damper is complicated. Since it is necessary to incorporate a damping force variable function such as a hydraulic circuit, the internal structure becomes complicated and the equipment cost increases.

In particular, for small-scale seismic isolation of lightweight structures such as floor seismic isolation, equipment seismic isolation, rack seismic isolation, and housing seismic isolation, both improvement of seismic isolation performance during small and medium earthquakes and reduction of damage during large earthquakes In addition to the above, it is not easy to use the damping force variable damper at present because the damping device is required to be downsized and simplified.

The present invention has been made in view of the above circumstances and maintains high seismic isolation performance at the time of a small earthquake by a simple structure without using a separate detecting means, etc. An object of the present invention is to provide a mounting structure for a damping device that can prevent displacement while exhibiting a displacement suppressing function to reduce the risk of collision.

In order to solve the above-mentioned problems, the invention according to claim 1 is an attachment of a damping device which is arranged in a horizontal direction and one end of which is connected to a lower structure via a gap mechanism and the other end of which is connected to an upper structure. In the structure, the one end of the attachment structure of the damping device is provided so as to be relatively displaceable between the stoppers provided on the lower structure side, and a preset resistance force is provided between the one end and the lower structure. For the following horizontal force, damping that allows the relative displacement between the one end and the lower structure when the one end and the lower structure are integrated and when the horizontal force exceeding the resistance force acts. comprising a mounting structure of the device, a seismic isolation device attached to the said lower structure and the upper structure, the attenuation device which is attached to the superstructure, and the gap mechanism attached to the lower structure, the damping A mounting bolt that connects the device and the gap mechanism, and the mounting bolt and the damping device integrally constitute the mounting structure, the one end being the mounting bolt, and the other end. The part is the damping device, the mounting bolt is inserted into the damping device and the gap mechanism, a mounting portion is formed in the damping device, the mounting bolt is inserted into the mounting portion. The gap mechanism has a metal object and a plate, the metal object is fixed to the lower structure, and the metal object is formed with an elongated hole between the stoppers. Is inserted into the elongated hole, the mounting bolt is inserted into the plate, the elongated hole is arranged between the plate and the mounting portion in the insertion direction of the mounting bolt, At this time, as the plate slides on the surface of the metal object, the mounting bolt moves inside the elongated hole in the sliding direction of the plate.

The invention according to claim 2 is the invention according to claim 1, wherein the plate is an outer plate, the gap mechanism further includes an inner plate and a movable piece, and the mounting bolt is provided on the inner plate. Is inserted, the inner plate is arranged between the elongated hole and the mounting portion in the insertion direction of the mounting bolt, the movable piece is arranged inside the elongated hole, The movable piece is attached to the outer circumference of the attachment bolt .

Further, the invention according to claim 3 is the invention according to claim 2 , wherein the metal object is formed in a U-shape, the elongated hole is a first elongated hole, and the metal object is a second elongated hole. Slot is formed, the outer plate is a first outer plate, the inner plate is a first inner plate, the gap mechanism further comprises a second outer plate, a second inner plate and a nut. , The mounting bolt is inserted into the second outer plate and the second inner plate, the mounting bolt is inserted into the second elongated hole, in the insertion direction, the second length The hole is arranged between the second outer plate and the second inner plate, and the second inner plate is arranged between the second elongated hole and the mounting portion in the insertion direction. It is characterized by.

According to the invention described in any one of claims 1 to 3, by setting the resistance force to the magnitude of the horizontal force desired to be generated between the damping device and the lower structure at the time of a small earthquake, In the case of (for example, a ground motion level of 0.2 Gal or less), the damping device and the lower structure are integrated, and the vibration locally generated due to the rattling of the gap portion against the small-amplitude vibration of the upper structure caused by the slight vibration. Can be prevented.

Further, when a horizontal force exceeding the above resistance force is applied during a small-to-medium earthquake (for example, at a ground motion level of 0.2 Gal or more), the damping device becomes relatively displaceable between the stoppers provided in the lower structure, The seismic isolation device can exert a high seismic isolation effect. At this time, if, for example, a frictional force is used as the resistance force, energy absorption performance can be imparted by the hysteresis damping effect of the frictional force generated during the relative displacement.

Then, when a large earthquake such as a medium earthquake or more (for example, 20 Gal or more at the seismic motion level) occurs and the relative displacement amount increases, one end of the damping device abuts the stopper to prevent further movement. Therefore, the damping device operates to exert a strong damping force, and the displacement suppressing function of the stopper can avoid the risk of collision with surrounding structures.

At this time, since the gap portion is provided between one end of the damping device and the lower structure, the vibration generated by the impact force when the damping force of the damping device changes is directly transmitted to the upper structure side. It can be prevented.

As a result, high damping performance is exhibited with weak damping force during small earthquakes, and strong damping force is switched over with medium earthquakes and above, thereby exerting a displacement suppression function while preventing damage to the mounted object and reducing collision risk. be able to.

Moreover, since it can be realized by a simple structure without using a separate detecting means such as a conventional damping force variable damper, it is possible to perform small-scale seismic isolation for lightweight structures such as floor seismic isolation and equipment seismic isolation. Also, it can be used as a suitable damping device.

It is a front view which shows one Embodiment of the attachment structure of the damping device which concerns on this invention. It is the top view which expanded the principal part of FIG. FIG. 3 is a sectional view taken along line AA of FIG. 2. 5 is a graph showing the relationship between relative displacement and damping force in Example 1. 7 is a graph showing the relationship between relative displacement and damping force in Example 2. 9 is a graph showing the relationship between relative displacement and damping force in Example 3. 9 is a graph showing the relationship between relative displacement and damping force in Example 4.

1 to 3 apply the damping device mounting structure according to the present invention to an oil damper mounting structure arranged as a damping device in a seismic isolation layer of a lightweight seismic isolation structure such as floor seismic isolation or equipment seismic isolation. FIG.
As shown in FIG. 1, in this lightweight seismic isolation structure, an upper structure (floor, equipment, rack, house, etc.) 2 is supported on a rigid sliding bearing (or a lower structure (structure floor, seismic isolation foundation, etc.) 1 It is supported by a laminated rubber bearing 4 which also serves as a linear guide 3 and a restoring mechanism.

An oil damper (damping device) 5 is provided as a damping device on the seismic isolation layer formed between the lower structure 1 and the upper structure 2.
The oil damper 5 is arranged in the horizontal direction, one end 5a is connected to a reaction force block 1a integrally formed with the lower structure 1 via a gap mechanism 6, and the other end 5b is a lower part of the upper structure 2. Are linked to.

2 and 3 show the gap mechanism 6, and reference numeral 10 in the drawings denotes a metal object fixed to the reaction force block 1a. The metal 10 is a plate-shaped member formed in a U-shape in a plan view, and is fixed by protruding the opposing side 11 from the reaction force block 1a toward the oil damper 5 side. The facing sides 11 are formed with elongated holes 12 extending in the horizontal direction.

Further, ring-shaped outer plates 13 and inner plates 14 are arranged on both surfaces of the opposite side 11 with the elongated holes 12 sandwiched therebetween. On the other hand, the one end portion 5a of the oil damper 5 is provided with a cylindrical mounting portion 15.

Then, the mounting bolt 16 is inserted into the mounting portion 15 of the oil damper 5 from the outer plate 13 and the inner plate 14 of the one opposing side 11, and is further passed through the inner plate 14 and the outer plate 13 of the other opposing side 11. The nut 17 is screwed into the threaded portion that is extended outward.

In the drawing, reference numeral 18 is a movable piece in which the mounting bolt 16 is inserted and is interposed between the outer plate 13 and the inner plate 14, and reference numeral 19 is the inner plate in which the mounting bolt 16 is similarly inserted. It is a washer for gap adjustment interposed between 14 and the attachment part 15.

As a result, the mounting bolt 16 integrated with the one end 5a of the oil damper 5 is provided so as to be relatively displaceable with respect to the lower structure 1 between both ends (stoppers) of the elongated hole 12. Then, cushioning members 20 made of an elastic material such as rubber are attached to both ends of the elongated hole 12 in order to reduce a collision with the movable piece 19 provided on the outer periphery of the mounting bolt 16.

Further, in the gap mechanism 6, the nut 17 of the mounting bolt 16 is tightened and an axial force is applied to the mounting bolt 16, so that mainly between the outer plate 13 and the outer surface of the facing side 11 of the metal object 10. An initial frictional force (resistive force) is applied, and during normal times (for example, at a ground motion level of 0.2 Gal or less), sliding (slip) does not occur between the outer plate 13 and the facing side 11.

Here, by adjusting the tightening force of the nut 17, the initial frictional force (resistive force) is reduced between the oil damper 5 and the substructure 1 at the time of an expected medium-small earthquake (for example, 0.2Gal or more at the earthquake motion level). The size is set so that sliding (sliding) occurs between the inner and outer plates 13 and 14 and the facing side 11 when a horizontal force exceeding a horizontal force generated between them acts.

Further, the length dimension of the long hole 12 is such that the gap length d between the operating piece 19 and the end of the long hole 12 is such that the oil damper 5 and the lower portion will fall in the middle earthquake expected (for example, about 20 Gal at the seismic motion level). It is set so as to have one-sided amplitude of the relative displacement generated between the structure 1 and the structure 1.

Further, in the mounting structure of the oil damper 5, the main body portion of the oil damper 5 is held by the hanging member 21 from the upper structure 2 side.

According to the mounting structure of the oil damper 5 having the above-described configuration, the tightening amount of the nut 17 is adjusted so that the frictional force between the inner and outer plates 13 and 14 of the gap mechanism 6 and the facing side 11 can be adjusted by the oil damper during a small earthquake. 5 is set to the magnitude of the horizontal force desired to be generated between the lower structure 1 and the lower structure 1, the oil damper 5 and the lower structure 1 are integrated in a normal state, and It is possible to prevent the vibration locally generated due to the rattling of the gap mechanism 6 with respect to the swing of a small amplitude.

Further, when a horizontal force exceeding the above-mentioned frictional force acts at the time of a small earthquake, sliding occurs between the inner and outer plates 13 and 14 and the outer surface of the facing side 11 of the metal object 10, so that the mounting bolt 16 has the elongated hole 12. By making it relatively displaceable in the interior, a high seismic isolation effect due to the rigid slide bearing (or linear guide) 3 and the laminated rubber bearing 4 can be exhibited, and energy is also reduced by the hysteresis damping effect of the friction force generated during the relative displacement. Absorption performance can be imparted.

Then, when a large earthquake such as a medium earthquake occurs and the relative displacement amount becomes large, the operating piece 19 of the mounting bolt 16 abuts on the cushioning material 20 provided at the end of the elongated hole 12 and further. Is prevented, the oil damper 5 operates to exert a strong damping force, and the displacement suppressing function of the elongated hole 12 makes it possible to avoid the risk of collision with surrounding structures.

As described above, according to the above gap mechanism 6, when the one-sided amplitude a exceeds the gap length d between the operating piece 19 and the end of the slot 12, the one-sided amplitude δ In the range of (=2×d−a), the damping force is low, and in the range exceeding the one-sided amplitude δ, the damping force is switched to the high damping force.

As a result, without using separate detection means like the conventional damping force variable damper, the simple structure enables high seismic isolation performance during small earthquakes, and displacement during medium earthquakes and above while preventing damage to the mounted object. The restraint function can be exerted to reduce the risk of collision.

Further, since the gap mechanism 6 is provided between the oil damper 5 and the lower structure 1, it is possible to prevent the vibration generated by the impact force when the oil damper 5 operates from being directly transmitted to the upper structure 2 side. be able to. In addition, since the cushioning material 20 is provided at the end of the long hole 12, the impact force generated when the oil damper 5 operates can be mitigated.

In addition, since the main body of the oil damper 5 is held by the suspension member 21 from the upper structure 2 side, the weight share of the oil damper 5 acting on the gap mechanism 6 is reduced, and the frictional force is adjusted. It is possible to improve accuracy.
As a result, a remarkable effect is exerted particularly when used for small-scale seismic isolation in a lightweight structure such as floor seismic isolation or equipment seismic isolation.

In order to verify the effect of the present invention, an oil damper having a damping coefficient of 15 N·s/cm is used as the oil damper 5, and the resistance force (friction force) in the gap mechanism 6, the gap displacement d, and the excitation wave With respect to the following Examples 1 to 4 in which the type and the amplitude a (mm) were changed, the relationship between the displacement and the damping force was obtained by analysis.

(Example 1)
Excitation: Sine wave with amplitude a=60 mm Resistance (frictional force) of the gap mechanism 6: 5N
Gap displacement: d=50mm

(Example 2)
Excitation: Sine wave with amplitude a=100 mm Resistance (frictional force) of the gap mechanism 6: 25N
Gap displacement: d=60mm

(Example 3)
Excitation: Sine wave with amplitude a=90 mm Resistance (frictional force) of the gap mechanism 6: 5N
Gap displacement: d=70mm

(Example 4)
Excitation: Earthquake response wave with maximum amplitude a=90mm Resistance (frictional force) of the gap mechanism 6: 5N
Gap displacement: d=70mm

4 to 7 show analysis results of the above Examples 1 to 4, respectively.
In Example 1 shown in FIG. 4, the damping force becomes low in the range of one-sided amplitude δ (=2×d−a)=2×50−60=±40 mm, and switches to the high damping force in the range exceeding this. .. Further, in Example 2 shown in FIG. 5, the damping force becomes low in the range of one-sided amplitude δ=2×60−100=±20 mm, and switches to the high damping force in the range exceeding this.

Further, in Example 3 shown in FIG. 6, the damping force is low in the range of the half amplitude δ=2×70−90=±50 mm, and is switched to the high damping force in the range exceeding this. Further, in Example 4 shown in FIG. 7, the damping force is low in the range of one-sided amplitude δ=2×70−90=±50 mm, and is switched to the high damping force in the range exceeding this.

As described above, according to the mounting structure of the oil damper 5 having the above-described configuration, the gap displacement d is set according to the length dimension of the elongated hole 12, and the tightening force of the nut 17 with respect to the mounting bolt 16 is adjusted so that the resistance force ( By setting the frictional force) to an appropriate value, it is possible to easily switch to a weak damping force during a small earthquake and switch to a strong damping force during a moderate earthquake or higher.

In addition, in the said embodiment, although the case where the elongate hole 12 provided in the opposing side 11 was used as a stopper was demonstrated, this invention is not limited to this, A big earthquake generate|occur|produces, and between upper and lower structure. Various forms can be adopted as long as they have a function of abutting one end of the damping device to prevent further movement when the relative displacement amount of is increased.

1 Lower structure 2 Upper structure 5 Oil damper (damping device)
5a One end 5b The other end 6 Gap mechanism 12 Long hole (stopper)
20 cushioning material 21 suspension member

Claims (3)

A mounting structure for a damping device, which is arranged in a horizontal direction and has one end connected to a lower structure via a gap mechanism and the other end connected to an upper structure, wherein the one end of the damping device mounting structure is The stopper is provided so as to be relatively displaceable between the stoppers provided on the lower structure side, and the one end and the lower structure are provided between the one end and the lower structure for a horizontal force equal to or less than a preset resistance force. And a damping device mounting structure that allows the relative displacement of the one end portion and the lower structure when the horizontal force exceeding the resistance force is applied,
A seismic isolation device attached to the said lower structure and the upper structure,
A damping device attached to the superstructure,
Said gap mechanism attached to the substructure,
It comprises a mounting bolt that connects the damping device and the gap mechanism,
The mounting bolt and the damping device are integrated to configure the mounting structure,
The one end is the mounting bolt, and the other end is the damping device,
The mounting bolt is inserted in the damping device and the gap mechanism,
A mounting portion is formed on the damping device,
The mounting bolt is inserted in the mounting portion,
The gap mechanism has a metal and a plate,
The hardware is fixed to the lower structure,
An elongated hole which is between the stoppers is formed in the metal object,
The mounting bolt is inserted through the elongated hole,
The mounting bolt is inserted in the plate,
In the insertion direction of the mounting bolt, the elongated hole is arranged between the plate and the mounting portion,
A seismic isolation device, wherein the mounting bolt moves inside the elongated hole in the sliding direction of the plate as the plate slides on the surface of the metal object during an earthquake. The plate is an outer plate,
The gap mechanism further includes an inner plate and a movable piece,
The mounting bolt is inserted in the inner plate,
The inner plate is arranged between the elongated hole and the mounting portion in the insertion direction of the mounting bolt,
The movable piece is arranged inside the elongated hole,
The seismic isolation device according to claim 1, wherein the movable piece is attached to an outer periphery of the attachment bolt . The hardware is formed in a U shape,
The slot is the first slot,
A second elongated hole is formed in the metal object,
The outer plate is a first outer plate,
The inner plate is a first inner plate,
The gap mechanism further comprises a second outer plate, a second inner plate and a nut,
The mounting bolt is inserted in the second outer plate and the second inner plate,
The mounting bolt is inserted through the second elongated hole,
In the insertion direction, the second elongated hole is arranged between the second outer plate and the second inner plate,
The said 2nd inner plate is arrange|positioned between the said 2nd long hole and the said attachment part in the said insertion direction, The seismic isolation apparatus of Claim 2 characterized by the above-mentioned .

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